I have a similar problem. Based on what I read in the materials that came with the solar charger, it should fully charge with a few hours sun. My solar charger faces due west and gets direct sunlight for at least five plus hours a day. However, when I check the battery charge level, it seems to be very slowly going down. It was 100% when I installed it just over three weeks ago. Now it’s at 86% even after full sunlight for the past four hours. What is going on? Is the charger not working. The battery level would suggest it isn’t.